Place rice in a medium saucepan with enough water to cover by about 1 inch. Gently swish grains in the pan with your fingertips until the water becomes cloudy; drain. Repeat 3 or 4 times, until the water remains almost clear. Cover with 1 1/2 cups cold water; let soak for 30 minutes.ring the rice and water to a boil over medium-high heat. Cook, uncovered, stirring occasionally, until most of the liquid evaporates from the surface, 4 to 6 minutes. Cover the pan and reduce the heat to the lowest setting; cook for 5 minutes. Remove from the heat and let sit undisturbed for 5 minutes.
Heat oil in a small skillet over medium-high heat; add mustard seeds. When the seeds begin to pop, cover the pan until the popping stops. Reduce heat to medium; add cashews and cook, stirring, until golden brown, 30 seconds to 1 minute. Remove from the heat; add lime juice, cilantro (or kari leaves), chiles (or jalapeno), turmeric and salt. Add the mixture to the cooked rice; mix well.
Brown-Rice Variation: If using brown basmati rice, rinse as directed in Step 1 then soak in 2 cups water. In Step 2, bring rice and water to a boil over medium-high heat. Reduce the heat to low, cover and simmer until the water is absorbed and the rice is tender, 25 to 30 minutes. Remove from the heat and let sit for 5 minutes. Proceed with Step 3.